String them along - Cat and Mouse style....
eg Who is my accuser / What did they say /
Hint / indicate that you intend to take Legal Counsel as the matter has some complexities -
Also hint / suggest that the lawyer would accompany you at any meetings with them AND that you will record the proceedings for purposes of Transparency.
Wife and I threatened with lawyers - and we have a lady counsel friend who is chomping at the bit to get involved - and they have yet to pursue us again - but we are totally shunned al the same [but not entirely by all ......very interesting developments in our case]
HQ wont be pleased with the fact that they sent a letter ! You have a black and white document now.
Meticulously record everything - written and verbal !!!
Where does the "lady" involved here feature in matters [IF you don't mind me asking that]? Is she your accuser?